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Rough drawings of rectricial morphology of select Mesozoic pennaraptors* in dorsal view. Not to scale.

*Pennaraptora is a newly-coined name for the group containing the last common ancestor of Oviraptor philoceratops, Deinonychus antirrhopus, and Passer domesticus and its descendants.

Oviraptorosaurs: Tails typically short, but very strong, likely to enhance use of tail feathers in visual displays. In Caudipteryx (and probably Protarchaeopteryx), a frond of feathers was present only at the tail tip, but Similicaudipteryx had large feathers along the entire length of the tail. A "bilobed" morphology where the feather frond was split into two distinct lobes on each side of the tail was once a popular interpretation for Caudipteryx, but this was based on the notion that the holotype specimen had preserved only one side of the feather frond. Newer interpretations suggest that both sides of the frond were preserved, though superimposed on top of one another.

Dromaeosaurids: Tails had limited vertical range of motion except at the base, but retained reasonable lateral flexibility. All specimens with well-preserved rectrices have a feather frond of sorts at the tip of the tail (and there is unpublished evidence that the frond in Microraptor extended down at least half the tail's length). A similar rectricial arrangement is seen in Scansoriopteryx. Some (but not all) Microraptor specimens preserve a pair of particularly long tail feathers at the tail tip.

Archaeopteryx: Rectrices form a large frond along the entire length of the tail. One well-preserved specimen shows a V-shaped split at the tail tip, but this may potentially have been the result of molting. Similar rectricial arrangements are seen in Jinfengopteryx and Anchiornis.

Jeholornis: Palm-shaped frond present at the tip of the tail, formed by narrow rectrices. A fan of coverts may have been present at the tail base, though there are many varying interpretations of this feature. (A very well preserved specimen figured in this review paper strongly suggests to me that a covert fan was indeed present.)

Epidexipteryx: Tail short with four very long ribbon-shaped rectrices attached.

Sapeornis: Potentially among the most basal birds to have had a pygostyle homologous with that of modern birds. The tail frond is fan-shaped due to the short length of the tail, but it almost certainly was not a mobile folding fan as seen in modern birds. This may represent the basal condition for short-tailed avialans.

Confuciusornithiforms and enantiornithines: Many had a pair of ribbon-shaped rectrices, but some individuals/taxa lacked them, probably reflecting sexual dimorphism. Some show marked oval-shaped expansions at the tips of their rectrices. Paraprotopteryx had four rectrices and Shanweiniao had at least as many (and potentially more). Shanweiniao is the only known taxon in which the rectrices overlapped at their bases, potentially conferring some aerodynamic function. The rectrices of most well-preserved specimens show barbs present only at the tips, but those of Eopengornis have barbs present along the entire length. They may represent a transitional morphology between a Sapeornis-like rectricial arrangment and that of "typical" enantiornithines (a shift that happened independently in confuciusornithiforms).

Euornithines: A tail fan with a muscular folding mechanism (as seen in modern birds) probably first evolved within euornithines. Many Mesozoic euornithines preserve the familiar fan-shaped tail, though, like in present day, there was variation upon this theme, such as the forked tails in Schizooura and Iteravis that were achieved using different rectricial arrangements.

"Among the most basal birds to have had a pygostyle homologous with that of modern birds."

Not if Foth et al's phylogenetic analysis is correct…

Do you remember if there was a reason they included Deinonychus in their definition of Pennaraptora? Was it to account for topologies with avialan oviraptorosaurs (which hasn't popped up since… what, Benton 2004)?

They don't provide an actual reason for using Deinonychus. It may be to safeguard against avialan oviraptorosaurs, or (achieving the same result from a different perspective) to guarantee that deinonychosaurs are included.

Yes (and you didn't spell it wrong), but Chuniaoae has never been given a definition in the technical literature and there is reason to think that its original authors changed their minds about coining it at all, only leaving one use of it in the paper by accident.

Yes, the latter. Neither Anchiornis nor Jinfengopteryx ended up as troodonts in the latest analysis, for instance. They both had Archaeopteryx-like tails, for what it's worth, as I indicate in the description.